Gated blood pool tomography: a technology whose time has come.

Tomographic gated blood pool imaging is a natural extension of the technologies of planar gated blood pool scanning and rotating Anger camera single photon emission computed tomography (SPECT). The high photon flux, optimum 140 keV energy, and volume sampling of tomography permit reconstruction of the data in any perspective. The true three-dimensional nature of this process allows the evaluation of regional wall motion of all the cardiac chambers, unencumbered by overlapping structures. The heart can be viewed from any angle, including a long axis, short axis, apical four chamber, and a true inferior view. In addition to evaluation of regional wall motion, precise determination of chamber volumes and ejection fractions is possible. Early clinical experience has demonstrated the superiority of tomographic gated blood pool imaging over planar blood pool imaging for precisely defining subtle functional abnormalities. The enormous amount of data generated by this procedure taxes the capacity of most nuclear medicine computer systems. However, the availability of 32-bit processors and large amounts of image memory in new machines should ultimately reduce this processing time to less than ten minutes. The combination of complete visualization and quantitation suggests that a renaissance for blood pool imaging is on the horizon.